The recovery of lower limb function in stroke patients: which sequence of transcranial direct current stimulation combined with lower limb rehabilitation robot is most effective-A randomized controlled trial.

The sample size was small (54 participants), limiting the generalizability of the findings. Participants and therapists in the active groups could not be blinded due to the nature of the interventions, which may have introduced performance bias. The sequential group received 20 minutes more total intervention time than the synchronous group, making it difficult to separate the effect of timing from the effect of additional duration. The study only followed patients for four weeks, so long-term effects are unknown. All participants were in the early subacute phase (less than 70 days post-stroke), so results may not apply to chronic stroke patients.

The study was funded by the Natural Science Foundation of Shaanxi Province and the IIT Clinical Research Fund of The Second Affiliated Hospital of Xi'an Jiaotong University. No specific commercial conflicts of interest were declared in the provided text.

Do not assume the sequential group's inferiority is due to timing alone. The sequential group received 20 minutes more total treatment time than the synchronous group, so the difference in outcomes could be partly due to fatigue or attention effects rather than the timing of stimulation.